The Doctor is a space and time traveling alien, the protagonist in the fictional Doctor Who universe, who was created in 1963. Currently the Doctor is in its 13th incarnation, which is the form of a woman, a first.
The Doctor is a renegade Time Lord, who has vowed to do no harm and to help others. Whom has traveled across the cosmos, across time, and to other dimensions and realities. His two favorite worlds are his homeworld Gallifrey (the home of the Time Lords) and Earth, both which he defends ferociously. The Doctor has saved numerous civilizations, species, worlds, and galaxies, in addition to the many individuals whose lives he has saved. It's unknown how old the Doctor truly is due to all the time traveling and temporal anomalies / time locks the Doctor has experienced, but the Doctor claims to be over 800 years old.
The Doctor has fought many tyrants, empires, organizations, criminals, races, and entities both on Earth and in space. Of which it's greatest enemies are the Daleks, a race of intergalactic genocidal xenophobic cybernetic mutants whom pose the greatest threat to the universe. The Doctor has also fought several entities of the Mythos including Hastur and Yog-Sothoth, prevailing every time so far.
The Seventh Doctor intentionaly confronted the Elder Gods many times, one of his companions dying, until a sort of truce was eventually reached.
Although he hoped never to meet Nyarlathotep, one of his companions managed to convince a cultist that he was Nyarlathotep himself.
Behind the MythosEdit
Andrew Cartmell, the script editor of the Seventh Doctor seasons (24-26), co-wrote a writer's guide for the expanded Doctor Who universe range of novel when it was taken of the air. In this he created a character known as "the Other" with mysterious but strong ties to the Doctor.
When asked by fans of the Other could be Nyarlathotep, he admitted not knowing who Nyarlathotep was.